Choice of boiler fittings

[phoenix01]

What boiler fittings to buy?
As a new member this is my first proper post so I hope that I am using the right protocol.
I have a 4" horizontal marine boiler kit to build and am in the process of sliding up the very steep learning curve. The aim is for a smart installation and I would welcome any thoughts on the choice of boiler fittings (preferably from UK suppliers) - safety valve, globe valve, check valve & level gauge. What makes a good or bad fitting. Is price any guide to quality.
BTW I do intend to consult a boiler certifier before starting construction, but I need to make the bushes first to complete the set of parts.
Thanks, James

[kno3]

Are you planning to use metric or imperial threads?

[phoenix01]

Are you planning to use metric or imperial threads?

Hello kno3, thanks for your reply. I will be using imperial ME threads. James

[kno3]

There are many suppliers in Britain. I have used fittings from:
http://www.ajreeves.com/ Click on shop and boiler fittings
There is also http://www.steamfittings.co.uk/ and others.

[phoenix01]

Many thanks. There is quite a variation in price, e.g. Reeves seem to be the most expensive. Is there a significant difference over the less expensive offerings. For example will the stem screw out of a cheap steam valve?

[derekwarner_decoy]

Hi PD's......phoenix01

With your standard unions etc....you get what you get get....a body + nut + solder cone ....& irrespective of the brand of manufacture

However some steam valves are designed as a metering/isolation valve & have preferred direction of flow to ensure that the metering is carried out in the designed manner [all to do with the flow of steam over the needle & the height of the inlet & outlet galleries within the valve body

The valve on the left was sold as 1/8" full bore, but has no direction markings......
The valve on the right [althought much smaller] was also sold as 1/8" full bore....but it does have a direction arrow...I suspect it is a Reeves globe valve #39/7061...I can see the same direction arrow stamping in the body

In our imperfect world....we model steam boaters are generally using these valves as isolation valves & not as controlable metering valves...... ....so maybe it is not necessary.....
The valve to the left requires undue force to make steam tight
The valve to the right required light thumb & forefinger force to make steam tight 

I have taken the valve on the left apart...there is no mark on the needle......I cannot see the corresponding seat area inside, however have lapped the needle to the seat with lapping paste to no avail

I would not purchase another el-cheapo metering/isolation valve such as this again .....Derek

PS1...I purchased the smaller steam valves [a pair] in Australia....but the design & handwheel look very similar to the Reeves variety.....#39/7061

[phoenix01]

Hi Derek. There had to be a reason for the substantial difference in price. Your experience is very helpful. Thanks very much. James